Trailer brake operating mechanism



Feb. 25, 1941. s, B. WINN 2,232,755L

TRAILER BRAKE OPERATING MECHANISM Original Filed Jan. 3, 1938 5 Sheets-Sheet l Gttornegs Feb. 25, 1941. 5, B WINN TRAILER BRAKE OPERATING MECHANISM Driginal Filed Jan. 3, 1938 5 Sheets-Sheet 2 Gttorneu 5 F61). 25, 1941. s. Q WINN TRAILER BRAKE OPERATING MECHNISM 5 Sheets-Shea OriginalFled Jan. 3, 1938 S. B. WINN TRAILER BRAKE OPERATING. MECHANISM F eb, 25, 1941 original Filed Jan. 3, 1958 5 sheets-sheet 4' Cttomegs Feb. 25, 1941. A s. B. wlNN 2,232,755

TRAILER BRAKE OPERATING MECHANISM Original Filed Jan. 5, 1938 5 Sheets-Sheet 5 Patented Feb. z5, 1941 2,232,755Y l TRAILER BRAKE O'PRATINGTMEHANISM- y Sidney B; Winn, Lapeer, Mich.` y Original applicationy January 3- 19318,r Serial No.

183,072. Divided-and this 1939, SerialNo. 277,343

application: June.v 5,

melanin- L lorica-13)" Thisfinvention relates,` generally t0 vtractortrailer. vehicles and more particularly to brake` applying mechanism therefor. f

, `This applicationV is adivision of. my co-pending application. entitled Tractor trailer.. coupling mechanism, led; January 3, 1938, Serial No. 183,072.

It is an object of` the vpresentinvention to provide, new .and improved.. brake operating mechanism forl trailers having. props arranged to be raised andlowered..

Another objectof'the invention isto provide for. a. trailerY of.A the above mentioned character brake operating mechanism which is, automatically operable. upon uncoupling` of such trailers from .tractors Another object of the invention is to provide-for trailers; new and improved brake operating mechanism including manually releasing; `automatically actuated holding mechanism for positively holdingthe brakes applied.

Other-objects of the inventionwill become apparentirom. the following description. taken in connection with the. accompanying drawings, in Which*- Figure 1 is a fragmental side--view ofa coupled tractor andtrailer, the trailerfbeing shown in vertical section; n

Fig.. 2 is a fragmental view ofthe trailer;`

Figs. 3' and4` are fragmental plan views; illustrating coupled and uncoupled vpositions respecftively;.

Fig; 5-V is a section'taken on the line 55 of Fig; 3;'

`1'fig.6 isa section taken on the-line 6-6 0fl Fig.' 4; V Fig; 7` is a section taken on thev line 'I-l of Fig. 3;

Fig: 8 is a sectionfsimilar-'to F'ig. 5, illustrating i the=lockreleased priorto movement of the king Fig; 9'fis a section taken on the' line 9--9 of Fig: 4:' i

Fig; 10 isfafragmentalsection, illustrating the f brake actuating levers;

- Figi 111 is anexploded perspective-view ofI the brakefactuating levers, and

Figs. 12, 13: and; 14 are elevations illustrating different positions of' a. detail. f

Like characters of reference are employed throughout'to designate corresponding parts.

A tractor I has the usual fifth vwheel 2f pivotallyl mounted thereon, the fifth .vheel having a slotl 3' (Figs. 7 and 8)' for the reception of'aking pin4 carried by the trailer 5. When the tractor and trailer are coupled, mechanism car'- ried by the fifthwheel' locks the king pin in the slot' 3. This invention relates to the mounting means for` the king pin and mechanisms associ'ated therewith on the trailer for performing certain service operations," and the means for locking.; tlie` king pin in theslot 3 has not been illustratedfinasmuch as itforms-no part of the invention.. l v

Mountedupon the forward vend of the` trailer 5' are; two parallel channel guides 6 receiving the rollers; 'I' which carry the-king pin supporting block-8; .The blockV 8 ismovable forwardly'and rearwardly ofvthextrailer in its guides 6 and is adapted to be locked'inf its'. rearmost position against forward movement', and also in its forward position, orV any stage between its rearmost position andits; forward position, against rear- Wardimovement. The means for locking the block innitsfrearmost position; as shown in Figs.` l, 3; 5and '7,- vcomprises'ra U-shap'ed locking'member 9 pivoted upon bracketseI Uwhereby it may beswung into` engagement` with a vertical` stud II on the block B. The U:-shaped lockingmember 9 is so mounted that'it iallsbyforce of 'gravity into engagementwith the stud II, when the block 8 is in: its rearmost position, to prevent forward movementA of-/theblock; The means for. preventing rearward movement of the block comprises a pawl: I2.- pivotedbetween two bars I3, which are attachedto the; block 8 and extend rearwardly ofthetrailer,- the pawl I2k being adapted to engage-r any one of' a lengthwisel extendingseries ofv ratchet; teeth I4.; The pawl I2 is mounted whereby, itzfalls' byffforce of gravity into engagement' witlrthe'teeth I4: x Mounted in thef block 8 is arocking lever I5, one end'fof which extends beneath the locking member.: The other end I6 of' the rocking lever has-a spring I'lfconnectedA theretofwhich acts thereon to rock said lever in avdirection to elevate the locking" member 9. rA cam-likeV lever Ilia4 extends underr the rocking lever end I6 and when the tractor is coupled tothe trailer, the :fifthY wheel .2 engages the cam-like lever Ia and' causesit to rock the lever I5 to Aa posi tion (seeFig. 7i) permitting the locking'member 9 toV engage thestud II, and thereby maintains they spring I'l'lcompressed. The spring I1 is comparativelyfstrong andaexerts a normal pressureof approximately several hundred pounds. Therefore, when the fifth wheel moves away from` the king pin, asit does in uncoupling, the canlike-f lever I 6a rides off the'top surface of the fthwheel andthe rocking lever I5 moves very rapidly, as a Iresult of the high spring pressure, from the position 'shown in Fig. V7 to that shown in Figs. 8 and- 9. Such movement of the lever, snaps the'locking member 9 out of engagement with thevstud I`I and thereby releases the block 8` whereby itr may move forwardly. I

The rocking lever I5`lalso engages anarm I8 on the pawl I2l andrmai'ntains the pawl I2 ele- 7. When the rocking lever I5 is moved, as shown in Figs, 6, 8 and 9, the arm I8 is released and the pawl I2 is permitted to fall into engagement with the teeth I4.

Adjacent to the forward end of the trailer is pivotally mounted a prop I9, adapted when lowered to support the forward end of the trailer,'

when the latter is uncoupled vfrom the tractor. The forward and rearward movements of the king pin block 8, above described, are utilized to elevate and lower the prop I9. ATo this end, a cross shaft 2D is provided with rollers 2I on opposite ends thereof which are received in channel guides 22, and the shaft is connected to the prop I9 by links 23. The parallel bars I3 are connected to a bar or bars I3a which is connected at 24 to a notched arm 25 pivoted upon the shaft 20. When the bar I3a is moved rearwardly it tips the arm 25 upwardly and pushes the shaft 20 and links 23 rearwardly to elevate the prop, as shown in Fig. 1. When prop lowers, the bar I3a moves forwardly, as shown in Fig. 2, and the arm 25 tips forwardly whereby it engages a rigid element 26, and thereby lowers and locks the prop in a lowered position.

l The free wheels of the trailer are equipped, as usual, with brakes. One of the brakes 21, is shown in Fig. 2, and it will be understood that both brakes are connected, as by the link 29 and arm 29 to a rotatable shaft 30. A single arm 3| rigid on the shaft 30 is connected by a link 32 to an arm 33 which is rigidly mounted on a transversely extending rotatable shaft 34. The arm4 33 has a laterally extending lug 35.

Loosely mounted on the shaft 34 is a lever 36 having an integral arm 31 with a curved link 38 connected thereto. To the free end of the link 38 is connected a tension spring 39 and the other end of the spring is connected by tension adjusting meansy 39a to a, rigid transverse member 40. The spring 39 normally urges swinging movement of the lever 36 about the shaft 34 whereby its end 4I engages the laterally extending vlug and swings the arm 33, in a `direction to apply the brakes. An extension 42 is provided on the locking member 25 which engages a lug 43 on the lever 36, when the blockl is in or near its Vrearmost position, to swing the lever 36 in opposition to the pressure of the spring 39 whereby the usual brake shoe retracting springs (not shown) may release the brakes.

Adjacent and parallel to the shaft `34 is a rotatable shaft 44 having an arm 45 rigidly mounted thereon and adapted to engage the lug 43 on the lever 36. Externally of the trailerjfrarne member 46 the shaft 44 carries a pawl 41 and a spring 48 acts upon the pawl to urge rotation ofthe pawl and shaft 44 and thereby maintains the arm 45 in contact with the lug 43. Also'externally of the trailer frame 46 the shaft 34 is provided with a manually operable lever 49 having ratchet teeth 50 thereon. i l

. As shown in Fig. 12, the mechanism is positioned whereby the brakes are released, the lever 36 being held in its rearmost position by the extension 42, and the lug 43 holding the arm 45 in a position wherein the pawl 41 is spaced from the path of movement of the ratchet teeth 5I). When the extension 42 is withdrawn from contact with the lug 43, the lever 36 is swung forwardly by the spring 39, and the spring 48 urges the pawl 41 to the position shown in Fig. 13, wherein it engages the ratchet teeth to hold the lever 36 against retrograde movement.

A dog 5I is pivoted concentric with the pawl 41 and is adapted to be manually moved into engagement with lugs 52 and 53 on the lever 49 to prevent rotation of the shaft 34. With the lever 49 positioned as shown in Fig. 14, the dog 5I may be placed in engagement with the lug 52 to hold the shaft 34 against movement in a. direction causing brake application. In other words, the

dog positioned as here indicated prevents application of the brakes. When positioned in engagement with the lug 53, as indicated in dot and dash lines in Fig. 14, the dog 5I holds the brakes applied. .p p

As shown in Figs. l, 3, 5 and '1, the tractor is coupled to the trailer, the king pin block 8 is in its rearmost position and is positively held in this position by the locking member 9. The extension 42 is in engagement with the lug 43 and the brakes are thereby held released. Assuming, for an understanding of the uncoupling operation, that the king pin holding means on the fifth wheel 2 is released to permit uncoupling, the tractor` is moved. It will be noted that the pressure of the spring 39 and also the weight of the pivoted prop I9 are actingon the bar I3a in a manner to advance the king pin sliding block 8. Thus, when the tractor is moved and the fifth wheel 2 advances until the cam-like lever I6a registers with the. slot 3, the lever I5 is actuated by the spring I1 to snap the locking member 9 from engagement with the stud II, as shown in Fig. 8, so that the pressure of the spring 39 and the weight of theprop I9 initiate forward movement of the king pin block 8. The brakes are thus applied and the prop I9 lowered until it contacts the ground `or assumes the position where it is fully lowered as shown in Fig. 2. The pawl I2,- being released simultaneously with the lock 9, engages one of the teeth I4 to hold the block 8 and the prop I9 against retrograde movement. The pawl I2, it will be noted, holds the prop againstretrograde movement whether the prop is fully lowered or not and it is possible, therefore to uncouple on irregular surfaces.

If, during uncoupling as above described, the friction is great enough to cause movement of the tractor with the trailer, the brakes may be manually applied by means of the lever 49.

Should the release of the locking member 9 fail to result from the pressure of the spring I1, a lever 6U is engaged by the fth wheel 2 and is rocked to impart movement to the links 6I which are connected to arms 62 on the locking member 9. A spring 61a acts upon the links 6I to hold the lever 60 in its normal position. This movement positively initiates movement of the locking member and overcomes any friction which might prevent movement by the pressure of the spring.

With the tractor and trailer uncoupled, the forward end of the trailer is supported by the prop I9. As the tractor is again backed under the trailer, in the coupling operation, the fifth wheel strikes the cam-like lever I6a and the latter rocks the lever I5 whereby it engages the arm I8 and elevates the pawl I2. The locking member 9 is at this time riding on the bars I3 and the block 8 is free to move rearwardly. Continued movement of the tractor causes engagement of the end of the slot 3 with the king pin 4 and the block `8 is moved rearwardly, thereby causing the prop I9 to be elevated.

During the coupling operation the brakes are held applied by the pawl 41 until such time as the latter is released by operation of the arm `45, caused by swinging movement of the lever 36 when its lug 43 is engaged by the extension 42. At the time the pawl di is released, the stud Il is positioned whereby the locking member 9 falls into locking engagement therewith.

The type of prop here shown is well known to Y the art, but in the instant case the locking pawl l2 cooperates in a novel manner therewith. As shown in Fig. 2 the locking member 25 is in a locked position and cannot be released without moving the element i3d rearwardly. The element l3nt cannot move rearwardly at this time because the pawl l2 is operative to prevent rearward movement of the links I3. Therefore the pawl l2 comprises a lock for locking the lock 25 in a locked position. This function is important inasmuch as during coupling of the tractor to the trailer the locking member 25 is held locked until the fifth wheel engages the cam-like lever la and through rocking the rocking lever l5 raises the pawl I2. The coupling operation is almost completed, therefore, before the king pin block is moved to elevate the prop and the brakes willremain applied until coupling has been completed.

As a result of the locking functiony referred to immediately above it is impossible to elevate the prop unless the king .pin enters the slot in the fifth wheel. Ii the king pin rides on top of the fifth wheel the cam-like lever lct cannot be actuated and the king pin remains locked against movement relative to its guides.

Although a specic embodiment of the invention has been illustrated and described it will be understood that various changes may be made within the scope of the appended claims without departing from the spirit of the invention and such changes are contemplated.

What I claim is:

l. In combination with a trailer adapted to have a tractor coupled thereto, brakes on said trailer, yieldable means normally acting on said brakes for applying the same, releasable means for positively holding the brakes applied, and manual means for rendering said yieldable means ineffective and for releasing said releasable means.

2. In combination with a trailer adapted to have a tractor coupled thereto, brakes on said trailer, yieldable means normally acting on said brakes for applying the same, releasable means for positively holding the brakes applied, manual means for rendering said yieldable means ineffective and for releasing said releasable means, and means operable independently of said releasable means and said last-named means for positively holding said yieldable means ineiective.

3. In a trailer having a prop movable between raised and lowered position and having brakes, means acting to apply the brakes, means for overcoming said first-named means and operable in accordance with movement of the prop, and manually operable means for rendering said second-named means ineffective and for releasing said irst-named means.

4. In a trailer having a prop movable between raised and lowered positions and having brakes, means acting to apply the brakes, means operable to restrain said brake applying means and operable to release said brake applying means upon lowering of the prop, and releasable means for positively holding the brakes applied and actuated by said second-named means.

5. In a trailer having brakes and having a prop arranged to be raised and lowered, a lever operatively connected to the brakes, a second lever operatively connected to said first-named lever, means operable in accordance with movement of the prop and operatively connected to said second-named lever, and means for positively holding the brakes applied and operatively connected to said rst-named means.

6.In a trailer having brakes and having a prop arranged to be raised and lowered, a lever operatively connected to the brakes, a second lever operatively connected .to said iirst-named lever, means operable in accordance with movement of the prop and operatively connected to sai-d second-named lever, means for positively holding the brakes applied and operatively connected to said iirst-named means, and manually operable means for releasing said brake holding means.

7 In a trailer having brakes and having a prop arranged to be raised and lowered, a lever operatively connected to the brakes, a second lever operatively connected with said rst-named lever, spring means acting on said second-named lever to pivot said rst-named lever to apply the brakes, means operable in accordance with movement of the prop and operable to overcome said spring means, a third lever operatively connected with said second-named lever, and a holding device operable for positively holding the brakes applied and operatively connected to said third-named lever.

8. In a trailer having brakes and having a prop arranged to be raised and lowered, a lever operatively connected to the brakes, a second lever operatively 'connected with said rs't-name-d lever, spring means acting on said second-named lever to pivot said rst-named lever to apply the brakes, means operable in accordance with movement of the prop and operable to overcome said spring means, a third lever operatively connected with said second-named lever, a holding device operable for positively holding the brakes applied and operatively connected to said thirdnamed lever, and manually operable means for releasing said holding means.

9. In a trailer having brakes, a prop for the trailer and movable between lowered and raised positions, means acting to apply the brakes, releasable means for positively holding the brakes applied and controlled by said rst-named means, means operable in accordance with raising and lowering of said prop to control operation of said brake applying means, and means for rendering said first-named means ineffective and for releasing said releasable means.

10. In a trailer having brakes, a prop for the trailer and movable between lowered and raised positions, means operable to apply the brakes, control means operable in accordance with raising and lowering of said prop to control operation of said brake applying means, safety holding means actuated by said control means for releasably holding the brakes applied, and manually operable means for controlling operation of said brake applying means independently of said control means.

SIDNEY B. WINN. 

